Wong had been a member of the Pathway Home – a facility that looks after military veterans suffering from post-traumatic stress disorder (PTSD).

It forms part of the Veterans Home of California-Yountville, which houses around 1,000 elderly and disabled veterans.

California Highway Patrol assistant chief Chris Childs said the bodies had been found around 6pm, almost eight hours after the gunman slipped into a staff party.

Mr Childs said: “It’s far too early to say if they (the victims) were chosen at random.”

Image:Mr Childs said it was too early to say if the hostages were chosen at random

Image:The standoff lasted eight hours

Larry Kamer said his wife had been at the party and phoned him to say the gunman had entered quietly before letting some leave and taking others hostage.

Victim Jennifer Golick also called her husband to say she was being held – but nothing was heard from her after that, said her father-in-law.

Police evacuated the building and closed off roads when the standoff began.

An armoured police vehicle, ambulances and fire engines were rushed to the scene, located about 53 miles north of San Francisco.

Image:Police enter the Veterans Home of California

Wong exchanged fire with a sheriff’s deputy at around 10.30am but then went silent, despite repeated police attempts to contact him.

In a statement, Pathway Home paid tribute to the victims: “These brave women were accomplished professionals who dedicated their careers to serving our nation’s veterans, working closely with those in the greatest need of attention after deployments in Iraq and Afghanistan.”